Classifications

• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B60—VEHICLES IN GENERAL
  • B60N—SEATS SPECIALLY ADAPTED FOR VEHICLES; VEHICLE PASSENGER ACCOMMODATION NOT OTHERWISE PROVIDED FOR
  • B60N2/00—Seats specially adapted for vehicles; Arrangement or mounting of seats in vehicles
  • B60N2/24—Seats specially adapted for vehicles; Arrangement or mounting of seats in vehicles for particular purposes or particular vehicles
  • B60N2/42—Seats specially adapted for vehicles; Arrangement or mounting of seats in vehicles for particular purposes or particular vehicles the seat constructed to protect the occupant from the effect of abnormal g-forces, e.g. crash or safety seats
  • B60N2/427—Seats or parts thereof displaced during a crash
  • B60N2/42709—Seats or parts thereof displaced during a crash involving residual deformation or fracture of the structure
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B60—VEHICLES IN GENERAL
  • B60N—SEATS SPECIALLY ADAPTED FOR VEHICLES; VEHICLE PASSENGER ACCOMMODATION NOT OTHERWISE PROVIDED FOR
  • B60N2/00—Seats specially adapted for vehicles; Arrangement or mounting of seats in vehicles
  • B60N2/02—Seats specially adapted for vehicles; Arrangement or mounting of seats in vehicles the seat or part thereof being movable, e.g. adjustable
  • B60N2/22—Seats specially adapted for vehicles; Arrangement or mounting of seats in vehicles the seat or part thereof being movable, e.g. adjustable the back-rest being adjustable
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B60—VEHICLES IN GENERAL
  • B60N—SEATS SPECIALLY ADAPTED FOR VEHICLES; VEHICLE PASSENGER ACCOMMODATION NOT OTHERWISE PROVIDED FOR
  • B60N2/00—Seats specially adapted for vehicles; Arrangement or mounting of seats in vehicles
  • B60N2/24—Seats specially adapted for vehicles; Arrangement or mounting of seats in vehicles for particular purposes or particular vehicles
  • B60N2/42—Seats specially adapted for vehicles; Arrangement or mounting of seats in vehicles for particular purposes or particular vehicles the seat constructed to protect the occupant from the effect of abnormal g-forces, e.g. crash or safety seats
  • B60N2/4207—Seats specially adapted for vehicles; Arrangement or mounting of seats in vehicles for particular purposes or particular vehicles the seat constructed to protect the occupant from the effect of abnormal g-forces, e.g. crash or safety seats characterised by the direction of the g-forces
  • B60N2/4214—Seats specially adapted for vehicles; Arrangement or mounting of seats in vehicles for particular purposes or particular vehicles the seat constructed to protect the occupant from the effect of abnormal g-forces, e.g. crash or safety seats characterised by the direction of the g-forces longitudinal
  • B60N2/4228—Seats specially adapted for vehicles; Arrangement or mounting of seats in vehicles for particular purposes or particular vehicles the seat constructed to protect the occupant from the effect of abnormal g-forces, e.g. crash or safety seats characterised by the direction of the g-forces longitudinal due to impact coming from the rear

Definitions

• the present invention relates to a backrest support mechanism for a motor vehicle seat, comprising a support plate, attached to either of a seat squab and a seat backrest, a first connection between the support plate and either of the squab and the seat backrest, a second connection between the support plate and either of the squab and the seat backrest.
• Whiplash injuries may be prevented or reduced if the seat is arranged in such a way that the backrest can move and/or tilt under energy absorption causing the buttocks and the torso of the occupant to accelerate more gradually.
• the movement of the backrest is provided by a support mechanism mounted between the seat frame and the back of the seat.
• the support mechanism comprises two pivotal links of which one is connected to a deformable element in a support plate.
• An object of the present invention is to provide a seat backrest support mechanism which reduces at least some of the above problems .
• a seat backrest mechanism according to the introduction is further characterised in that at least a part of the support plate is adapted to deform plastically to permit rearward movement of the seat backrest relative the seat squab when subjected to a predetermined force.
• a seat backrest support mechanism which may reduce or eliminate the risk for injuries to an occupant involved in a rear impact is provided.
• a compact seat backrest mechanism that is less complex is achieved. Since the support plate is adapted to deform plastically additional deformation element may not be needed. Thus an arrangement having few parts is provided.
• the support plate may have a weakened section where the support plate is deformed when subjected to a predetermined force, in order to adapt the support plate for deformation at a predetermined location. Thus it is possible to control at which location and at which load the support plate is deformed.
• a weakened section may be formed by a notch or aperture in the support plate.
• the weakened section may be defined by a section with thinner material thickness than the rest of the support plate.
• the support plate may define a force transmitting structure supporting the backrest. That is the backrest may be supported by the deformable support plate itself. Thus a seat backrest mechanism having few parts is achieved.
• the first connection may further comprise an engagement element attached to the seat squab and a guiding edge formed in the support plate, wherein relative movement between the seat squab and the support plate is guided along the guiding edge.
• the engagement element may be a shaft attached to the squab and received in an aperture formed in the support plate.
• the engagement element may be a pin or a roller.
• the engagement element may be attached to the backrest and the guiding edge may be formed in the seat squab.
• the first weakened section may be adapted to deform plastically when the support plate being in a second displacement position.
• energy is absorbed during a subsequent rearward pivotal action of the support plate.
• the deformation of said first weakened section may be possible when the engagement element has performed a relative movement along the guiding edge to a second displacement position.
• a first parallel movement of the backrest due to relative movement of the engagement element along the guiding edge from a initial position to a second position may be possible without deformation of the support plate.
• Subsequent rearward pivotal movement under energy absorbing deformation of the support plate is then possible.
• the first weakened section may be formed adjacent to the guiding edge.
• the mechanism may further comprise an element to prevent relative movement of the support plate in ordinary use.
• the element may for instance be a breakable pin attached to the seat squab and received in a recess formed in the support plate.
• a breakable pin may be attached to the support plate and received in a recess formed in the squab.
• the mechanism may further comprise a retaining element to retain the engagement element in its initial position relative the guiding edge until a first threshold force is excessed.
• the retaining element may be deformable in order to permit relative movement between the support plate and the seat squab when subjected to a first threshold force. Thus when a first threshold force is excessed the retaining element is gradually deformed during the generally parallel movement of the backrest.
• the retaining element may be resilient in order to deform elastically .
• the retaining element may be releasable. Thus the retaining element can be released during the subsequent rearward pivotal action. That is the retaining element is active during the first generally parallel movement of the backrest.
• the support plate may have a second weakened section where the support plate is deformed when subjected to a predetermined force.
• the support mechanism may be deformed at the second weakened section to permit a parallel movement of the backrest in a first phase of a rear impact and the support plate may be deformed at the first weakened section to permit a tilting movement of the backrest in a second phase of a rear impact.
• the second connection may be a link arm having a first and a second pivoting joint.
• Contact may be established between a part of the support plate and a part of the second pivoting joint after a first parallel movement of the backrest in order to stop further parallel movement of the backrest.
• a locking means may be provided in order to prevent the support plate from returning to its initial position from a first deformation position.
• Fig. 1 shows a side view of selected parts of a vehicle seat in which a backrest support mechanism according to an embodiment of the present invention is mounted.
• Fig. 2a shows a side view of the back rest support mechanism in fig. 1 in a first and initial retained condition.
• Fig. 2b shows a side view of the mechanism in fig. 1 in a second condition.
• Fig. 2c shows a side view of the mechanism in fig. 1 in a third and final condition.
• Fig. 3 shows a side view of selected parts of a vehicle seat in which a backrest support mechanism according to another embodiment of the present invention is mounted. Detailed description of preferred embodiments
• Fig. 1 shows a backrest support mechanism 1 according to an embodiment of the present invention.
• the mechanism 1 is mounted in a vehicle seat 2 between a seat squab 3 and a seat backrest 4 to support the seat backrest 4.
• the backrest support mechanism 1 comprises a support plate 5 attached to the backrest 4, by suitable attachment means 6, and connected to the seat squab 3 by means of a first mechanical connection 7 and a second mechanical connection 8.
• the support plate 5 has two weakened sections 9 and 10 where the support plate 5 is deformed plastically at different stages of a rear impact.
• the support plate 5 is deformed at the first 9 and the second 10 weakened sections respectively due to forces on the seat when the vehicle is involved in a rear impact situation.
• the weakened sections 9 and 10 are formed in the support plate 5 by a first recess 11 and a second recess 12 respectively. The function of the mechanism including deformation of the support plate in a rear impact situation will be described.
• the first mechanical connection 7 is formed by an aperture 13 in the support plate 5 receiving an engagement element 14, in this case a shaft, attached to the seat squab 3.
• the aperture 13 forms an open guiding edge 15.
• a guiding edge may be formed by a closed aperture.
• the second mechanical connection 8 is in this embodiment formed by a pivotal joint 16.
• the joint 16 is formed by a recess in the support plate 5 receiving a shaft attached to the squab 3.
• the shaft defines an axis for pivotal action of the support plate 5.
• a retaining element 17 is arranged between the engagement element 14 and a pin 18 attached to the support plate 5.
• the retaining element 17 is in this case a resilient pawl provided with a first recess for receiving the engagement element 14 and a second recess 19 partly enclosing the pin 18, see fig 1.
• Fig. 2a shows parts of a seat 2 in ordinary use.
• the support plate 5 is kept in a first position, see fig. 2a.
• the engagement element 14 is retained in the guiding aperture 13 due to forces from the retaining element 17. That is the retaining element 17 is acting to keep the engagement element 14 in its initial position in the aperture 13.
• the seat 2 and consequently the backrest 4 remain in a first position until the backrest 4 is subjected to a first threshold force.
• a first threshold force is excessed in case the car is involved in a rear impact situation where there is a risk of injuries to the occupant.
• this first threshold force will not be excessed during ordinary use such as adjustment of the seat by a occupant sitting in the seat using the seat length-, height- and angle adjustment, under normal driving conditions, or in a rear impact situation at very low speed. That is a certain crash severity is needed to initiate the rearward movement of the backrest relative the seat squab.
• a robust connection between the seat and the seat backrest is provided in ordinary use.
• the movement in this first phase is essentially a parallel displacement of the backrest 4 under preservation of the seat backrest angle.
• the support plate 5 is deformed at the second weakened section 10 until contact between the upper and the lower part of the recess 12 is established, see fig. 2b.
• the support plate 5 has been deformed in such a way that a stop that prevents further parallel movement of the backrest 4 has been formed in the support plate adjacent to the second weakened section 10, see fig. 2b.
• the position of the engagement element 14 in the guiding aperture 13 is changed during this first essentially parallel movement of the backrest, see fig. 2b. In the enlargement of fig.
• the retaining element is not shown to clearly illustrate the position of the engagement element 14.
• the guiding aperture is formed to allow a essentially parallel movement of the seat backrest under preservation of the seat angle in the first phase of the backrest movement.
• the support plate is moved from a first position, shown in fig. 2a, to a second deformation position, shown in fig. 2b.
• the back rest may then, in response to a continuing force applied by the torso of the occupant, pivot around the joint 16 toward a third displacement position, see fig. 2c.
• the shaft performs a relative movement along the guiding edge 15 until the engagement element 14 is stopped by the guiding edge 15 in the guiding aperture 13. That is when contact is established between the engagement element 14 and the part of the guiding edge 15 that forms a stop, see fig. 2c.
• Subsequent tilting is then possible since the support plate 5 is deformable at the first weakened section 9.
• the force that is needed to deform the support plate 5 at the first weakened section 9 may correspond to a second threshold force.
• the support plate As the backrest executes subsequent tilting the support plate is deformed at the first weakened section.
• rearward tilting movement of the seat back is possible due to the pivotal function of the second mechanical connection 8 and since the support plate 5 is deformable.
• energy is absorbed by the support plate.
• the support mechanism provides a controlled backward movement of the backrest in a rear impact situation.
• the retaining element 17 is released from the pin 18.
• a pivotal action around the joint 16 is provided.
• the second mechanical connection 8 is formed by a link arm 20 having a first pivoting joint 21 and a second pivoting joint 22 as shown in fig. 3.
• the support plate 5 has a first weakened section 9.
• a retaining element 17 that prevents movement of the support plate 5 in ordinary use is provided.
• the inertia will cause the buttocks of the occupant to apply a substantial generally rearwardly directed force to the lower part of the seat back. If the force acting on the seat excess a first threshold value the retaining element 17 will start to deform and/or deflect and consequently the seat backrest 4 is moved generally rearwardly relative to the seat squab 3.
• the guiding aperture 13 and the pivotal link arm 20 permit the support plate 5 to perform a parallel movement a certain distance without being deformed.
• the second mechanical connection 8 which in this case is a pivotal link arm 20 having a first pivoting joint 21 and a second pivotal joint 22, permits a parallel movement of the support plate 5 until contact is established between a part of the support plate 5 and a part of the second joint 22.
• the force that is needed to deform the support plate at the first weakened section may correspond to a second threshold force.
• the retaining function in ordinary use could be provided by adapting the pivotal joints with a predetermined resistance to rotation.

Landscapes

• Engineering & Computer Science (AREA)
• Aviation & Aerospace Engineering (AREA)
• Transportation (AREA)
• Mechanical Engineering (AREA)
• Seats For Vehicles (AREA)
• Chairs For Special Purposes, Such As Reclining Chairs (AREA)

Priority Applications (4)

Applications Claiming Priority (1)

Publications (1)

Family

ID=39766128

Family Applications (1)

Country Status (4)

Cited By (5)

Families Citing this family (2)

Citations (4)

Family Cites Families (3)

• 2007
  • 2007-03-22 EP EP07716081.0A patent/EP2121378A4/en not_active Withdrawn
  • 2007-03-22 WO PCT/SE2007/000278 patent/WO2008115103A1/en active Application Filing
  • 2007-03-22 JP JP2009554472A patent/JP5153794B2/ja not_active Expired - Fee Related
  • 2007-03-22 CN CN2007800521933A patent/CN101641235B/zh not_active Expired - Fee Related

Patent Citations (4)

Non-Patent Citations (1)

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